Schachar Ronald A, Mani Majid, Schachar Ira H
Department of Physics, University of Texas at Arlington, Arlington, TX.
California Retina Associates, El Centro.
Clin Ophthalmol. 2017 Sep 11;11:1625-1636. doi: 10.2147/OPTH.S144238. eCollection 2017.
To evaluate anterior chamber depth, central crystalline lens thickness and lens curvature during accommodation.
California Retina Associates, El Centro, CA, USA.
Healthy volunteer, prospective, clinical research swept-source optical coherence biometric image registration study of accommodation.
Ten subjects (4 females and 6 males) with an average age of 22.5 years (range: 20-26 years) participated in the study. A 45° beam splitter attached to a Zeiss IOLMaster 700 (Carl Zeiss Meditec Inc., Jena, Germany) biometer enabled simultaneous imaging of the cornea, anterior chamber, entire central crystalline lens and fovea in the dilated right eyes of subjects before, and during focus on a target 11 cm from the cornea. Images with superimposable foveal images, obtained before and during accommodation, that met all of the predetermined alignment criteria were selected for comparison. This registration requirement assured that changes in anterior chamber depth and central lens thickness could be accurately and reliably measured. The lens radii of curvatures were measured with a pixel stick circle.
Images from only 3 of 10 subjects met the predetermined criteria for registration. Mean anterior chamber depth decreased, -67 μm (range: -0.40 to -110 μm), and mean central lens thickness increased, 117 μm (range: 100-130 μm). The lens surfaces steepened, anterior greater than posterior, while the lens, itself, did not move or shift its position as appeared from the lack of movement of the lens nucleus, during 7.8 diopters of accommodation, (range: 6.6-9.7 diopters).
Image registration, with stable invariant references for image correspondence, reveals that during accommodation a large increase in lens surface curvatures is associated with only a small increase in central lens thickness and no change in lens position.
评估调节过程中的前房深度、中央晶状体厚度和晶状体曲率。
美国加利福尼亚州埃尔森特罗市的加利福尼亚视网膜协会。
健康志愿者前瞻性临床研究，采用扫频光学相干生物测量图像配准研究调节过程。
10名受试者（4名女性和6名男性）参与研究，平均年龄22.5岁（范围：20 - 26岁）。将一个45°分光器连接到蔡司IOLMaster 700（德国耶拿卡尔蔡司医疗技术公司）生物测量仪上，能够在受试者右眼散瞳状态下，分别在注视距角膜11 cm的目标之前和过程中，同时对角膜、前房、整个中央晶状体和黄斑进行成像。选择在调节前和调节过程中获得的、符合所有预定对齐标准且黄斑图像可叠加的图像进行比较。这种配准要求确保能够准确可靠地测量前房深度和中央晶状体厚度的变化。晶状体曲率半径采用像素棒圆进行测量。
10名受试者中只有3人的图像符合预定的配准标准。平均前房深度下降了 -67μm（范围：-0.40至 -110μm），平均中央晶状体厚度增加了117μm（范围：100 - 130μm）。晶状体表面变陡，前表面比后表面更明显，而在7.8屈光度的调节过程中（范围：6.6 - 9.7屈光度），晶状体本身并未移动或改变其位置，从晶状体核缺乏移动情况来看就是如此。
通过具有稳定不变的图像对应参考的图像配准发现，在调节过程中，晶状体表面曲率大幅增加，而中央晶状体厚度仅小幅增加，且晶状体位置无变化。
